Plum cv. Suplumeighteen

ABSTRACT

A plum tree characterized by its unusually large, early ripening fresh quality, red-purple fruit which are round and slightly oblate in shape with prominent lenticels. Trees of the variety are of medium size and bear fruit regularly.

This application is a continuation of application Ser. No. 07/131,177,filed Dec. 10, 1987 now abandoned.

This invention relates to the discovery and asexual propagation of a newvariety of hybrid plum tree, Prunus salicina cv. Suplumeighteen. Thetree is an early seasoned red plum bearing fruit of unusually large sizecultivated for fresh market use. It was discovered by John H. Weinbergerand Timothy P. Sheehan in Fresno, Calif., and has as its seed parentQueen Rosa (unpatented). Its pollen parent is not known.

The new variety cv. Suplumeighteen may be distinguished from otherpresently available commercial plum cultivars by the followingcombination of characteristics: Suplumeighteen is a red plum bearingearly ripening fresh quality fruit of unusually large size, round andslightly oblate in shape, having prominent lenticels, and a red-purpleskin color at full maturity. The new variety holds these distinguishingcharacteristics through successive asexual propagations by, for example,grafting and budding.

The new variety may be distinguished from its seed parent, Queen Rosa,in the following combination of characteristics: Whereas the skin colorof the fruit of Queen Rosa is red, the skin color of the new variety isa deeper red-purple color. Fruit of Suplumeighteen ripens about twoweeks earlier than does the fruit of Queen Rosa and its appreciablysmaller in size.

The pollen parent of the new variety is not known.

The accompanying drawing illustrates, in full color, a typical stem andleaves of the new plum tree and the ripe fruit is viewed from the stemend and in profile. The drawing also illustrates the fruit sectioned inhalf from end to end, one-half of the fruit shown with the stone removedfrom the flesh.

Throughout this specification, color names beginning with a small lettersignify that the name of that color, as used in common speech, is aptlydescriptive. Color names with capital letters designate values basedupon The R.H.S. Colour Chart of The Royal Horticultural Society ofLondon, England.

Plum trees of the new cultivated variety Suplumeighteen have beendeposited before the filing date of this application in an orchardlocated at 5090 East Church Ave., Fresno, Calif. and are identifiedthere by applicant's identification number 401-48.

The descriptive matter which follows pertains to plum trees of the newvariety grown in the environment of the San Joaquin Valley and isbelieved to apply to plants of the variety grown under similarconditions of soil and climate elsewhere.

TREE

The tree is of average size and average vigor. It is upright in habitand vase-formed in shape. The foliage tends towards open growth. Thevariety is half-hardy. The trees are productive, bearing their fruitregularly.

The trunk is of average thickness and the bark average in texture. Thebranches are average in caliper and are of medium smoothness. Thebranches have a dull surface appearance and carry an average number ofaverage-sized lenticels.

LEAVES

In general, leaves are of average size, having an average length ofabout 91/2 cm. and an average width of about 4 cm. Leaves are ellipticin outline and upfolded in profile. Leaf blade tips curve downwardly atan acute angle. The finely serrate leaf margin has no undulation. Theleaf apex is cuspidate to broadly acuminate; the leaf base is U-shaped.Leaves are of average thickness.

Leaf color on the upper surface is near Green 137B in color. The upperleaf surface is smooth, with no hairs present and is semi-glossy. Thelower leaf surface is near Green 137C in color, weak in glossiness withno hairs present. The lower leaf surface is rugose in texture and has adull surface appearance.

The petiole is of average length and average thickness. There areusually two medium-sized globose glands positioned on both the leaf baseand petiole. Glands are red in color. Stipules are persistent.

Leaf buds are very small and avoid in shape. Their position, relative tothe shoot, is slightly held out and their support is small and notdecurrent.

Bud burst is early for the class.

Anthocyanin coloration in the flowering shoots is absent. Internodelength is average and buds are of average density. Flowering shoots aredistributed on spurs, one year old shoots, and older wood. The ratio ofwood (leaf) buds to flowering shoots is 1:2.

FLOWERS

Flower buds are average in size and average in length. Their shape isobtuse and positioning is free. Pubescence is abent. Flower bud color isbrown.

Flowers attain full bloom, on the average, around the fourth week ofFebruary which is early, as compared with similar varieties in thegrowing area of Fresno, Calif. Duration of bloom is average, about 14days. The diameter of the fully open flower is average, about 2 cm., androsaceous in shape. Petals are free. Color of the fully opened flower isWhite 155D.

Peduncles are of average length and of average thickness, with no hairs.

The receptacle is of average depth. Pubescence of the inner and outersurfaces is absent.

Sepals are positioned adpressed to petals and are ovate in shape.Pubescence of the inner and outer surfaces is absent. There are noflowers bearing double sepals present.

There are no flowers bearing double petals. Petals are of average size,about 0.8 cm., and circular in shape. Claw length is average and thereis weak margin waviness present. The base angle is average. The upperpetal margin is entirely divided. Pubescence of the inner and outersurfaces is absent. Color of the inner and outer surface is White 155D.

The position of the stigma is level as compared with anthers. Anothercolor just before dehiscence is yellow. Pollen color is yellow. Stamensare perigynous.

Pistils are almost always one in number. Supplementary pistils areabsent.

Pubescence is absent in the ovary. Pubescence at the base of the styleis absent.

FRUIT

The fruit, as now described, was eating ripe in early June, 1986. Thesize of the fruit of that stage of its development is uniformly large insize, having an axial diameter of about 5 cm. and a transverse diameterin the suture plane of about 6 cm. Fruit are practically uniform,symmetrical and globose in shape. The position of the maximum diameteris towards the middle. The fruit is symmetric about the suture line.Fruit ripens early in the season and is well adapted for market use andto serve fresh. Keeping quality of the fruit is average and shippingquality is average.

The suture line is distinct and shallow extending from the base but isdiscontinuous at the apex. The ventral surface is rounded throughoutboth sides, with equal lips. The apex is slightly depressed. The pistilbase does not persist. There is no pubescence at the apex.

The stem cavity is rounded, with the suture showing on one side. Thedepth of the cavity is about 11/2 cm., and its breadth about 1.3 cm. Nomarkings ar present. The base of the fruit is rounded. Its apex isrounded to slightly depressed in shape. The pistil point is apical andslightly depressed in shape.

The stem is of average length, about 1 cm., and adheres strongly to thestone.

The skin, which is of average thickness and of average texture, istenacious to the flesh and shows no tendency to crack during the dryseason. Reticulation is absent. Skin color at maturity is aroundRed-Purple 59A. Down is wanting and a bloom is present. Skin possessesno roughness.

The color of the flesh is reddish, around Red 46A, and the surface ofthe pit cavity is near Red 53A. The amygdalin content is wanting andjuice is present in abundant to moderate amounts. The flesh has anaverage sugar content. Flesh texture is average in texture and meaty.Fibers are fine, tender and few in number. Fruit ripens evenly toproduce fruit of good eating quality. The flavor is delicate and thearoma wanting. The ratio of stone to flesh is low.

The stone is semi-free, adhering to flesh along both dorsal and ventraledges. Fibers of the stone are short and parts from flesh smoothly,retaining short fiber-like threads along the ridges. The stone is ofmedium size, being about 21/2 cm. in length, and about 21/2 cm. inbreadth. The width at the stalk end of the stone is about 0.3 cm. andabout 1 cm. in thickness. The angle of the stalk end is a right angle.The form of the stone in profile is generally elliptical and cuneatetowards the base. The form is ventral view is sub-globular. The stone'sbase is straight, its apex acuminate. The hilum is oblong. The positionof the stone's maximum breadth is toward the middle and the sides aregenerally equal. The surface of the stone is ridged near the base andthere is a partly developed outgrowing keel. The ridges are continuousand jagged towards the base. The ventral stone edge is thin and withouta wing throughout. The dorsal stone edge is narrow and shallow withnarrow grooves towards the base. The color of the stone is near Orange26A. The stone has a slight tendency to split during the dry season.

What is claimed is:
 1. A new variety of plum tree, the variety beingparticularly distinguished and characterized by its early-ripening freshquality fruit of unusually large size, round and slightly oblate inshape, having prominent lenticels, and red-purple skin color atmaturity, substantially as herein shown and described.